SALABERRY-DE-VALLEYFIELD, Que. - It is the longest sentence ever handed down in Canada for a case of impaired driving - life in prison - and it's still not as tough as Crown prosecutors wanted.

A Quebec judge ultimately decided not to give prosecutors the legal prize they were hoping for: dangerous offender status for Roger Walsh, which would have made him the first drunk driver slapped with that designation.

But the judge still set legal history Wednesday by handing a life sentence to the "incorrigible" repeat drunk driver - which, according to several experts, has never happened before.

Still, Crown attorney Joey Dubois left the courtroom Wednesday imagining what might have been. He had hoped the case might establish a new precedent, with dangerous-offender designation and the additional safeguards it offers.

"By asking that the accused be declared a dangerous offender, we submitted a scenario that seemed well adapted to the situation with Mr. Walsh in all of the circumstances and conformed to our interpretation of the law," Dubois said.

"Justice (Michel) Mercier concluded the dangerous offender legislation was not meant to apply to offenders who commit this kind of crime."

Walsh, 57, was handed the ruling in a courtroom west of Montreal. He pleaded guilty to mowing down Anee Khudaverdian, a wheelchair-bound mother, last October after a night of binge drinking.

It was her 47th birthday. It was his 19th drunk-driving conviction.

Quebec court Judge Michel Mercier ruled that he couldn't in good conscience put Walsh back on the street, after experts deemed he could simply never fight off the bottle.

"You are incorrigible," Mercier said.

"Every measure taken in the past has failed. You are incapable of quitting drinking."

The victim's sister, Clara Khudaverdian, said the sentence was a strong one, but it would be up to politicians in Ottawa to make clear why recidivist drunk drivers can't qualify as dangerous offenders.

"We lost an opportunity, but we made history," Clara Khudaverdian said.

"A life sentence has never been given out ... I think it's something that we should celebrate. I hope its going to send a message."

Over 300 people in Canada have been declared dangerous offenders. Walsh would have been the first drunk driver subjected to a designation which has, until now, been reserved for the worst criminals like murderers and serial rapists.

In practical terms, however, Wednesday's life sentence could wind up being just as harsh.

Walsh would have had a chance, either way, to seek parole after seven years; the difference with dangerous offenders is that once they're freed they're monitored more strictly and, if they reoffend, they can then be locked up indefinitely.

Veteran Quebec criminal lawyer Benoit Gariepy, who was not involved in the case, noted it's rare enough for a judge to hand down the maximum prison sentence allowed under the law.

"This kind of sentence is only offered when the judge considers he's facing the worst of the criminals in the worst-case scenario," Gariepy said.

"In Mr. Walsh's case, he decided that he was faced with the worst of the criminals."

Prosecutors have now tried on at least three occasions - including in Ontario and Alberta - but no Canadian judge has ever granted a dangerous-offender tag for an impaired driving conviction.

The Crown had been hopeful that it could make history here because of recent changes in federal law that might have made it easier to get the label applied.

MADD Canada's Andrew Murie lamented the failed attempt and said he believed that down the road, the label will get slapped on a repeat drunk-driver who kills someone.

In the meantime, he said the Walsh sentence sends a message across the country.

"I think it recognizes the impact of drunk driving for victims and their families," Murie said. "Twenty years ago you wouldn't get that kind of recognition, so that's important as well."

Walsh pleaded guilty last December to running over Anee Khudaverdian in October 2008 after a night of heavy drinking. The wheelchair-bound mother was out with her dog, on her birthday.

The Crown was eager to test a 2008 Criminal Code amendment, to see if it could get the dangerous-offender designation stuck to Walsh.

With an absence of jurisprudence for applying the status in cases like this, the judge says he examined transcripts from the debate in Parliament last year when the Criminal Code was amended.

"It's clear that the intent of the legislator was not to include the infraction committed by the accused under the definition of dangerous offender," Mercier wrote, adding that it wasn't up to him to change the law.

The 2008 change allows prosecutors to seek the dangerous-offender status with a lengthy prison term - in Walsh's case, the crown sought 20 years, followed by 10 years of close surveillance - as opposed to an indeterminate prison sentence.

It was introduced in the Tories' Tackling Violent Crime Act.

Under the old rules, the dangerous-offender designation automatically meant an indefinite prison stay and was reserved for the worst violent criminals. Now, someone with the designation can get a fixed prison sentence but if they breach conditions once they're freed, they could be thrown back in jail indefinitely.

Walsh's lawyer, Jacques Vinet, had proposed a 10-year sentence. He said he was surprised by the sentence length.

"I'm surprised because the Crown attorney was asking 20 years and the defence was asking 10 years and the judge gave more than that," Vinet said.

"(But) I'm not surprised that he did not agree with the dangerous offender request."

He said he would speak with his client about whether to appeal the sentence.

Anee Khudaverdian was propelled into a ditch after being struck by Walsh's minivan. Walsh kept driving and was arrested less than 10 kilometres away after driving into a ditch himself.

The court heard he had more than double the legal blood-alcohol limit of .08 in his system.

Walsh's 18 previous impaired driving convictions and 114 previous convictions in total for assault, uttering threats, breaking and entering and theft were entered into evidence.

In addition to the life sentence, Walsh was also sentenced to two years for the additional charges he faced - hit and run causing death and probation violations.